1. Field of the Invention
The present invention relates to a display device, and particularly to a liquid crystal lens-type 3D display device in which a liquid crystal display panel having a lens function is arranged on the display surface side of a display panel for displaying an image.
2. Description of the Related Art
A display device by which an image can be viewed by switching two-dimensional (2D) display and three-dimensional (3D) display by naked eyes without using eyeglasses includes, for example, a first liquid crystal display panel that displays an image, and a second liquid crystal display panel that is arranged on the display surface side (viewer side) of the first liquid crystal display panel to forma parallax barrier allowing different rays to enter the right and left eyes of a viewer at the time of 3D display. In such a liquid crystal display device in which 2D display and 3D display can be switched, the orientation of liquid crystal molecules of the second liquid crystal display panel is controlled, so that a refractive index in the second liquid crystal display panel is changed, areas for lenses (lenticular lenses, cylindrical lens arrays or the like, generically referred to as cylindrical lenses) that extend in the vertical direction of the display surface and are provided in parallel in the horizontal direction are formed, and light of pixels corresponding to the right and left eyes is sorted to view points of the viewer.
As the liquid crystal lens-type 3D display device with such a configuration, there is, for example, a 3D image display device described in Japanese Patent Application Laid-Open No. 2010-224191 (corresponding US Patent Application Publication No. 2010/0238276A1). In the display device described in the publication, comb-like electrodes are formed at a pair of upper and lower transparent substrates that are arranged to face each other through a liquid crystal layer. With this configuration, voltage applied to the electrodes of the upper and lower transparent substrates is controlled to be able to control the switching of 2D display and 3D display, and the number of parallaxes can be controlled at the time of 3D display.